Intravenous sodium thiosulphate for vascular calcification of hemodialysis patients - a systematic review and meta-analysis.

BACKGROUND Vascular calcification is a common comorbidity among patients with chronic kidney disease (CKD) indicating major cardiovascular events. This study aimed to evaluate the effects and safety of intravenous sodium thiosulphate (STS) for vascular calcification in CKD patients. METHODS Electronic databases were searched for clinical trials that provided data comparing outcomes among patients treated with and without STS. PRISMA guidelines were followed. Efficacy was assessed using calcification scores and arterial stiffness. Safety was examined by analyzing adverse symptoms, electrolytes, and bone mineral density (BMD). Random-effects models were performed. Meta-regression and sensitivity analysis were done. The risk of bias was assessed using Cochrane tools. RESULTS Among the 5601 publications, 6 studies involving 305 participants (mean age: 56 years, male: 56.6%) with all participants on maintenance hemodialysis met eligibility criteria. For efficacy, the progression in Agatston scores in the coronary arteries (107 patients, mean difference (MD): -241.27, 95%CIs: -421.50, -61.03) and iliac arteries (55 patients, MD: -382.00, 95% CIs: -751.07, -12.93) was lower in the STS treated group compared with controls. The increase in pulse wave velocity was lower in the STS group (104 patients, MD: -1.29 m/s, 95% CIs: -2.24 m/s, -0.34 m/s). No association was found between the change in calcification scores and STS regimen. For safety, gastrointestinal symptoms (e.g. nausea) and increased anion gap acidosis were noted. No reduction in BMD by STS was observed. CONCLUSIONS Intravenous STS may attenuate the progression of vascular calcification and arterial stiffness in hemodialysis patients. Large and well-designed randomized controlled trials are warranted.